1. Field of the Invention
The present invention relates to continuous monitoring and quality parameter measurements in wireless broadband networks.
2. Description of the Related Art
In a wireless networks it is important to ensure good quality for the data traffic in the network. Quality can be verified and efficiently maintained by monitoring the functionalities of the wireless network with appropriate apparatus and procedures. The monitoring of the network reveals whether desired connection or services are available or whether a sufficient quality level for the connection is reached. Furthermore, monitoring is used for revealing any security attacks performed by a third party on a radio signal interface or through other interfaces.
New applications which often are provided by e.g. WLAN networks, WiMAX technologies and in Flash-OFDM technologies, require larger capacity and better quality than earlier. One such application is ‘Voice over IP (VoIP) over WiFi (wireless fidelity)’ which is also called VoFi. Other demanding applications include video streaming, video conferences (e.g. Netmeeting) and a so-called triple play functionality which means video, voice call and file transfer simultaneously over packet data network.
Wireless networks also regularly suffer from technology related issues significantly impacting to end user experience. Certain models or versions of wireless network equipment and user equipment may be incompatible. Amount of combinations is so high that testing everything against each others is impossible task for equipment manufacturers. These types of issues cause regularly problems with users accessing and using wireless services. Another typical phenomenon in wireless networks is “sleeping cell” syndrome. This means that cell may be visible to end users, but cannot provide any traffic or service. This may be related to a fault in the equipment, where each software version may behave differently in this sense. True end user experience depends on the full end-to-end functionality of the network, including wireless connection and all related wired infrastructure towards desired other network users or server offering services to the end user. The monitoring of the radio interface only is not sufficient. On the other hand, the monitoring of the wired connection only, is not sufficient either. Full visibility to true service quality requires complete end-to-end monitoring capability. Prior art systems are not capable of detecting these kinds of network behavior and thus, this makes the network vulnerable to degraded service quality.
Furthermore in prior art, wireless intrusion detection prevention systems (WIDPS) have been developed. The WIDPS uses measurement stations which are able to measure traffic in the network in a passive manner, RF signal level and overall noise level. WIDPS measurements are focused on data security monitoring and their capability to monitor end-to-end service quality is very limited. WIDPS apparatuses are able to disconnect an intruder from the network by a specific disassociation command. The first shortcoming with the WIDPS is that due to modest RF and antenna technology, it requires a vast amount of monitoring stations in the network area in order to work properly. Another shortcoming in the WIDPS solution is that the monitoring station requires a wired connection to the LAN. A further problem in the prior WIDPS solutions is that they enable only passive measurements and provide no end-to-end service quality visibility or information about the bottlenecks in the network. Furthermore, WIDPS does not have support for mobility, like GPS positioning of the monitoring station.
One known solution in prior art is based on WLAN switches. Each switch control a number of base stations and the switch can change configuration of each base station or change parameters for each base station. Therefore, the switch can define a certain controlled base station or multiple base stations as monitoring stations. Such monitoring stations are able to perform data security monitoring as in the WIDPS technology. This functionality and shortcomings are comparable to WIDPS systems. Additional issues with the switch-based solution is that it works only with Wireless LAN systems, scales poorly to larger configurations and requires a dedicated connection between the switch and access/monitoring point. Due to high operative cost related to dedicating transmissions lines to each access/monitoring point, this makes it practically impossible to manage a spread out network with this solution. Additionally, the base stations and the switches need to be provided by the same manufacturer. The switches are gateways for all the traffic. A fault in the switch may take down the whole wireless network under it. This leads to the need of using constantly two parallel WLAN switches in business applications that require high reliability. This even further increases the amount of switches and the costs in the switch-based solutions. Finally, a disadvantage is that the switch-based solution is non-mobile and it is not suitable for measuring the quality of service in view of the end user.
Furthermore in prior art concerning local area networks, there are solutions where data is transferred between desired servers and desired end user computers. Different data transfer protocols may be used and the solutions are based on software installed on the servers and computers. This is a wired technology for monitoring data traffic and for the transfer of the monitoring results. The main problem in these solutions for LAN is the lack of support for any RF measurements or for any data security measurements through radio interface. Thus they do not support any mobility, any wireless technologies or centralized network management that are crucial for any wireless network.
In WiMAX and cellular networks, there exist systems which monitor the traffic through internal interfaces of the network. These interfaces are between the base station and the fixed network and thus, no radio signal interfaces are covered at all with such monitoring systems. These systems do not offer full end user experience monitoring, they lack support for mobility and location related measurements. In wireless networks, location information is necessary to report accurately network performance.
The main problem in prior art is that the end-to-end service quality for the large and spread out wireless broadband networks cannot be monitored in any efficient and reliable manner.